Pneumatic foot support



Nov. 15, 1949 w, w, DAVIS 2,488,382

PNEUMATIC FOOT SUPPQRT Filed June 7, 1946 2 Sheets-Sheet l ZZZ/3712274277 Z27. Jar/.215

M @Wk Nov. 15, 1949 w. w. DAVIS PNEUMATIC FOOT SUPPORT 2 Sheets-Sheet 2 Filed June 7, 1946 27192322755 21 .Ua W's Patented Nov. 15, 1949 TED S TATES l ra-TEN 2,488,382, I

PNEUMATIC F0011 "SUPPORT "WhitmanW. Davis, Burbank, 'Calif.

Application June 7, 1946,- Se1 ia"i -No. "6753'54 1 Claim.

This invention relates to cushioned foot supports and, although not thereto restricted, is adapted particularly to the insertable "and removable type of insert or pa'd, constructed 'of two or more plies of suitable material, such as rubber, canvas-reenfcr'ce'd or cord-'r'eenforced rubber, leather, "or otherwisaat least twin of the plies being adapted to define between them exteriorly isolated chambers or cells, adapted to sealedly contain "a nuidgsuch as slycerine' ornther liquid, or'aiga's or gaseous'inixtu're,fsuch as air.

The chambers uncellsareherein referred to as pneumatic or air chambers "o'r cells'b'ecauseair is one of thereconim'enlied'Tluidsftheword, air, when employed herein, referring to air, or alternatively to any other suitable fluid. Any one or some orall of said plies are not ne'cessari'ly coextensive "with the entire structure, which is divided into a'plura1=chamber=constituting part and into a solid, generally attenuated, part. The

term, -solid, when employed herein, refers to the part ofthesupportwherein no definite, "deliberately designedairehainber or cell obtains and thatconsists 'of one or a 'plurality'of "mutually adjoining layers of suitable, "preferably resilient, material. 'su'ch'a structure would be conceivably a 'layer'of sponge rubber sheathed on both sides with canvas=reenforced rubber or plain "sheet rubber or leather or a combination ofthe f'oregoing and/or 'othermaterial's.

'Obj'eCt'aLIId aidvallifa'gebfiny"ihliiitiiih "Collsists in'tlie provision ofscieiitific correction for abnormal funct'ioning'oi" the human "foot, whether acquired or congenital and whether it derives frominlis'c'le or ligament weakness or strain or the like, as Well as in the provision of alleviation for non-correc'tible cases of the foregoing and of alleviation for not-yet s'urgicall-y corrected structural abnormalities, suchas, for "example, calcaneal spurs on theheel.

An important object and advantage consists in the provision of Wide individual applicability, in a'truly'scientific clinical-spirit, of every enact a number o f' 'basic invention-embodying supports to "every kind "of foot disorder for which the supports "may be indicated, the number of different'basic supportsbeing'deterniinedsolely by the necessary different lengths and widths in the various combinations, excepting for some supports provided with extensions of the basic structure corresponding air wells :or chambers for the support of the first phalangeal-metatarsal jciirit. Another object and-advantage consists in the provision of "structural economy without "sacrifice in the consistent durable performance of the support.

Additional objects and advantages manifest themselves thruout this specification, supplemented :by the accompanying drawings, for which views of typical, but not of allrpossible, embodiments have-been selected as 'suitable subjeets, the

views being schematic ones showing only the.

contours, in plan viewpof the various air-'"chambers and solid parts of the supports; the general art is so01d and well established that, topersdns skilled in it, a largenumber of "different materials and assembling-methods, all more or less satisfactory, are known, and any one of said materials and assembling methods are applicable to embodiments of the instant invention.

Figures 1, -2, 3,4, 5-and-6show said typical :embod-iments, which'are respectively indicated by lm-l-l, l2, l3, M and 15.

It -is manifest-that, in commontoall embodiments, there are an-inner or long longitudinal.

arch supportingchamber' or cell 6 and two auxiliary air chambers or 'cells, -altl'iough the invention can be embodie'din supports having, in addition tothe long longitudinal arch chamber, also referred to as the standard-cell or chamber, a, single or several auxiliary chambers, also re-' ferredto ascornplementary chambers or cells, from all of which, it is manifest, the standard chamber is inevery instance isolated. Referring to Figure-1, this support is provided with the half-elliptical, functionally complete heel-supporting heel-chamber "and the anterior or transverse arch-supporting simple metatarsal chamber 18, both communicating with one an- -other thru the there interveningmedialexchange duct [9. Marg-inally,but not in area, chamber I1 is coextensive with the-heel; the'incompletene'ss is 'with respect to the indentation 28, constituting a -recess to accommodate a calcancal spin on the heel. The position of chamber l a'corresponds with the foot locus ininiediately' behind the sec: ond, third and fourth metatarsal heads, also :re-

ferred to as metatarsals, just as the positionpf the main or standard chamber l6 corresponds to the medial side of the inner or long longitudinal 3 arch. In both cases, the two chambers allow the respective muscles and ligaments to shorten and strengthen for eventual unaided support thereby of the respective bones. Standard chamber 16 is always isolated because the kind and degree of 5 support for the long arch are substantially constant for all positions of the foot, whether when standing or in locomotion. When walking, the first impact is received on the heel, which impact is cushioned by the mass of air in chamber ll, this mass being immediately thereupon transferred under pressure therefrom thru the medial exchange duct l9 into the metatarsal cell 3, constituting it into a transitory cushion for receipt thereon of the next impact, whereupon the cycle begins to be repeated as long as the walking continues. In the case of communicating chambers, the total mass of air admitted to them is such as to inflate the anterior said chamber to a height of about three-eights of an inch, with the posterior said chamber collapsed, to which rule of inflation there is an exception, to which reference will be had during the description of Figure 4. My experience teaches me that, in the majority of cases, the three-eighths of an inch for infiation height is the most comfortable and beneflcial.

Referring to Figure 2, the simple metatarsal chamber l8 of Figure 1 has here been replaced by the modified metatarsal chamber [8A, designed to support the transverse or metatarsal arch behind the fifth as well as behind the second, third and fourth metatarsal heads, and also to support the short or outer longitudinal arch by the extension i8B'of cell I8A, which extension extends to the inner'incomplete heel chamber 20, with which chamber I8A therefore communicates. This extension, because of its relative attenuated form, functions somewhat similarly to the exchange duct 19 in Figure 1. This disposition of cells accords-lateral balance to the footand prevents inrolling or pronation.

Referring to Figure 3, the modified metatarsal chamber [8A communicates, thru the extension I813, with the cuboid chamber 2|, which adjoins and directly communicates with the outer incomplete heel chamber 22. Also present is an isolated scophoid cell 23, supporting the scophoid bone. Chamber 21 supports the cuboid bone. The function of cell 22 corresponds partly to the function of the complete heel cell in Figure 1.

Referring to Figure 4, the metatarsal cell [8 communicates, thru the medial exchange duct I9, with the enlarged inner incomplete heel chamber. 24, functioning similarly to cell in Figure 1, the indentation or recess for the calcaneal spur beingindicated by 35. Additionally included are the anterior marginal cell 25, the outer incomplete heel chamber 26 and the there intervening'o'uter exchange duct-2T, thethr'ee 60 sections being isolated'from'theother air sec- I tions but coacting with them in alleviation of or treatment of metat'arsalgia or Mortons'Toe; and cushioning the metatarsal heads. Inorder to assure that there is always at least'amas's'i65 of air in cell 25 suffi'cientforthe support of the" metatarsal heads, I inflate sections'25, 26 and? 21 with more air in-proportion to' their total volume than in the case of other combinations of communicating cells, referredto in thefsixth 70 paragraph of this specification. 'Theanterior marginal cell 25 constitutes a pier for. thejmeta v tarsal heads. a

Referring to Figure 5, a composite metatarsal cell, consisting of the first metatarsal cell section 29, the metatarsal arch cell section 30 and the fifth metatarsal cell section 3|, communicates, thru the exchange duct 32, with the combined cuboid and fifth metatarsal base cell 33, approximating a short or outer longitudinal arch cell, which in turn communicates, thru exchange duct 34, with modified heel cell 36, its calcaneal spur recess being indicated by 31.

Referring to Figure 6, a metatarsal cell [8 communicates, thru duct 19, with modified heel cell [1, whose calcaneal heel spur recess is indicated by 28. The numeral 38-.indicatesa first-phalangeal-metatarsal-joint cell correcting for hypermobility, shortness of the first metatarsal or looseness in said joint. Cell 38 is preferably mounted on a pier constituted from a relatively thick extension of the ply or plies constituting the solid part of the support. During the transfer of air from cell I8 to cell ll, a small amount thereof finds itself trapped in cell 39, which supthereof finds itself trapped in cell 40, which cushions the cuboid bone.

No attempt has been made to describe all pos-f sible combinations of cells as it would needlessly burden this specification and the accompanying drawings. With the exception of the isolated standard cell supporting the inner longitudinal arch, every other cell may be made to communicate with or be isolated from every and any other cell, or cells, this relationship being determined by the particular abnormality for which treatment or alleviation is indicated.

I claim: I

In a pneumatic foot support, the combination of a base member having an inflatable pneumatic cushion in a forward position to underlie the ball of the foot; a. second inflatable pneumatic cushion in a rearward position adapted to underlie the heel of the foot, the member having a restricted passageway connecting said pneumatic cushions, a sufficient supply of pneumatic fluid in said connected cushions to completely inflate only one of said cushions so that shifting of the weight from the heel to the ball of the foot during walking causes flow of'said pneumatic fiuid' from one to the other of the inflatable cushions I through said passageway; and a third and fully inflated pneumatic chamber on the member in a central position to underlie the principal arch of the foot, said chamber being pneumatically isolated from the cushions and from said passageway.

' WHITMAN W. DAVIS.

REFERENCES CITED The following references are of record in the file of this patent: V

UNITED STATES PATENTS Persichino Oct. 24, 1939 

